feat: a cleaner task list #42
kai wants to merge 3 commits into main from feature/task-list
Previa previewQueued
3f9c2a7
preview
Review the branch.
See it running.
Previa turns every GitHub pull request into its own live preview: the exact commit, built from your own Dockerfile, running at a private HTTPS link that's posted right on the pull request. Reviewers click, try it, and approve with confidence.
- 2 files
- to get started: a Dockerfile and a small config
- 1 link
- per pull request, the same on every push
- 48 h
- a preview stays up after it's published
- Free
- while Previa is in early access
pr-42-gc0uy9-k3x9q2ma.preview.ajaykathwate.dev/tasks
fernhill tasksserving 3f9c2a7
- Review pull request #42Today
- Write the release notesFri
- Plan the next sprintMon
+ Add a task
why
Why Previa
A screenshot is a moment.
A preview is a place to explore.
Reviewing a change should feel like using it. Previa puts the running commit one click away from the review, so nobody has to check out a branch to see what it does.
Frontend teams
Click through the real UI on every push, not a picture of it.
API & backend teams
Databases, migrations and background workers come along for the ride.
Open-source maintainers
Preview contributions from forks safely. Forks never get your secrets.
Product & QA
Test the real thing from a link on the pull request. No local setup.
@@ how your team reviews a pull request @@
- 1−Pull the branch, install, seed a database, just to click one button
- 1+Open the link on the pull request: that exact commit, already running
- 2−One shared staging server, where the last deploy wins
- 2+One preview per pull request, at a link that stays put
- 3−Screenshots in the thread, stale by the next push
- 3+One living comment, updated from Queued to Ready
- 4−"Works on my machine"
- 4+Everyone reviews the same running commit
- 5−Forgotten test environments left running for weeks
- 5+Removed on merge, and expired after 48 hours
play
Try it
Play with a pull request. Watch the preview follow.
Open it, build it, push new commits, merge it. A sped-up simulation of what Previa does on GitHub.
Build mode
feat: a cleaner task list #42
Not openedpreviabot commented · edited
no preview yet
fernhill/taskboard · demo
workflow
How it works
From pull request to preview,
in seven steps.
Build mode · you choose
The default. Nothing builds until you press Build latest commit. Builds five minutes after your last push. Every new commit resets the clock.
3f9c2a7
Step 01 · Notice
Previa notices the moment you open it.
As soon as a pull request is opened or updated, Previa picks it up, notes its latest commit and checks whether it can merge. Missed an update? Sync in the dashboard catches up in one click.
Opened#42 feat: a cleaner task list
branchfeature/task-list → main
latest commit3f9c2a7
authorkai
- pull request picked up
- latest commit noted
- merge status checked
Step 02 · Check
Nothing runs until it should.
In Manual mode, the default, you choose Build latest commit.In Automatic mode, a build starts five minutes after your last push. Right before it starts, Previa double-checks with GitHub. If anything changed, it waits.
You pressed Build latest commit5 minutes since your last push
- still open
- still on commit 3f9c2a7
- no merge conflicts
- your turn in the queue
Step 03 · Build
Exactly that commit, built cleanly.
Previa builds your own Dockerfile from exactly that commit, in a clean, isolated build with sensible time and size limits. The build log streams live while it runs.
- Preparing commit 3f9c2a7
- Step 1/5 : FROM node:22-alpine
- Step 3/5 : RUN npm ci
- Step 5/5 : RUN npm run build
- Image built
- Build finished in 1 min 12 s
your Dockerfileexact commitisolated buildlive log
Step 04 · Run
Its own space. Nothing else in reach.
Each preview runs on its own with firm CPU and memory limits. Your repository secrets are added when it starts (never for forks), and nobody can open it until its health check passes.
sizestandard · 1 vCPU · 1 GiB
health checkGET /health → 200
secretsadded at start
networkprivate to this PR
filesread-only · /tmp writable
lifetime48 hours
Step 05 · Share
One link for the life of the pull request.
Every pull request gets its own private HTTPS link with a random part nobody can guess. When you push again, the new version takes over only once it's healthy, so reviewers never land on a broken page.
https://pr-42-gc0uy9-k3x9q2ma.preview.ajaykathwate.dev
3f9c2a7serving → retired
8d41e0bhealthy → takes over
Step 06 · Report
Your team hears about it where they already are.
Previa keeps one comment on the pull request up to date, from Queued to Building to Ready with the link, and adds a check to the exact commit. The dashboard updates live, no refresh needed.
previa bot commented · edited
Previa preview: Ready
https://pr-42-gc0uy9-k3x9q2ma.preview.ajaykathwate.dev
commit 3f9c2a7 · expires in 48 hours
Previa previewsuccess · 3f9c2a7
Step 07 · Clean up
Merged or closed? It tidies up after itself.
When the pull request closes, the link stops working and the preview and its data are removed. A preview nobody closes expires 48 hours after it was last published. Building again brings it back at the same link.
- 1link switched off
- 2preview stopped
- 3build removed
- 4preview data removed
dashboard
previa.ajaykathwate.dev/dashboard
Demo data
Overview
Welcome back, kai
Your previews at a glance, from your own repositories.
Linked repositories43 available · 1 needs access
Open pull requests71 waiting its turn
Live previews5expire 48 h after publishing
Preview coverage71%5 of 7 open pull requests
From pull request to preview
Every step is readyNoticeNew pull requests and pushesReady
CheckMerge status before any workReady
BuildFrom the exact commitReady
RunIsolated, with limitsReady
ShareA private HTTPS linkReady
ReportComment and checkReady
Clean upOn close and expiryReady
Build requests
The newest request of each pull request.Pull requestCommitStatusRequested
#42 feat: a cleaner task listfernhill/taskboard3f9c2a7Succeeded6 min ago
#118 Add rate limitingfernhill/apib71e09cRunningjust now
#44 Dark mode for settingsfernhill/taskboard5c2d8aaWaiting its turn1 min ago
#39 Upgrade the charts libraryfernhill/taskboard1a9be44Failedthe image build failed
Workspace
Repositories
Pick a source to see its pull requests and previews.
Search repositories
All 4Available 3Needs access 1
fernhilltaskboard
Available4open pull requests
3live previews
Automatic buildsSynced 1 min ago
fernhillapi
Available2open pull requests
1live preview
Manual buildsSynced 3 min ago
fernhilldocs
Available1open pull request
1live preview
Manual buildsSynced 12 min ago
fernhillmobile
Needs access–open pull requests
0live previews
Previa can't read this repository yet. Grant access on GitHub.
taskboard pull requests
fernhill / taskboard /#42 · feat: a cleaner task list
Open
Kkai
feature/task-list
Automatic builds
Live updates
View on GitHub
Preview ready
Serving commit 3f9c2a7. It passed its health check.
https://pr-42-gc0uy9-k3x9q2ma.preview.ajaykathwate.devCopy
- Runs with
- PostgreSQL 17 and Redis 7. Data starts fresh on every rebuild.
- Outbound
- 1 approved destination.
Open preview
Rebuild preview
Tear down preview
Build logs
Latest commit
3f9c2a7MergeableBuild request
3f9c2a7Succeeded- Requested by kai · 6 min ago
- Finished 4 min ago · took 1 min 48 s
Deployed preview
3f9c2a7Live- Published 4 min ago
- Expires in 48 hours
#42 · feat: a cleaner task list
Build logs
fernhill/taskboard #42
Rebuild of commit 8d41e0b · requested by kai
RunningLive
Outputsecrets are maskedCopyDownload
fernhill /taskboard
Pull requestsSecretsOutbound
Stored secrets
Names only: values are encrypted and never shown again.NameUpdatedActions
MAILER_API_KEY2 days agoReplaceDeleteSENTRY_DSN5 days agoReplaceDeleteMAPS_API_KEY1 week agoReplaceDelete
Paste or import a .env file
ALGOLIA_APP_ID=FH8Q2LK1 ALGOLIA_SEARCH_KEY=••••••••••••••••Save secrets
- Added at start. Values reach your preview when it starts, never your build or image.
- Never for forks. Pull requests from forks get no secrets.
- Your values win. A secret replaces a variable with the same name in .previewrc.yaml.
- Masked in logs. Values are hidden from build and preview logs.
- Test credentials only. Use sandbox keys and test databases, never production ones.
features
Features
Everything between a push and a preview.
B·01
Manual or Automatic
Manual by default: you press Build latest commit. Or switch on Automatic and Previa builds five minutes after your last push.
you decide5 min quiet
B·02
Only buildable changes
Pull requests with merge conflicts don't build. Previa checks again right before it starts, so nothing runs by mistake.
CheckingConflictsOpen
B·03
Exactly that commit
Every preview is built from one exact commit, and your .previewrc.yaml is checked before anything runs.
exact commitconfig check
B·04
Your own Dockerfile
If it runs in Docker and answers HTTP, it runs on Previa: Node.js, Python, Ruby, Go, PHP, Java or a static site.
any language
B·05
Never drops a request
Every request is saved before it runs, so a hiccup never loses your build. It simply picks up again.
reliable
B·06
Safe for forks
Pull requests from forks build without your secrets or extra connections, and can't affect your other builds.
no secrets
R·01
Isolated by default
Each preview runs on its own, without admin rights, with a read-only file system and firm limits.
isolatedread-only
R·02
Pick a size
small 0.5 vCPU / 512 MiB, standard 1 vCPU / 1 GiB, or large 2 vCPU / 2 GiB, set in one line.
resource_tier
R·03
Databases included
Ask for PostgreSQL 17 or 16 and Redis 8 or 7. Each preview gets its own fresh copy and its connection details.
services
R·04
Setup & workers
Run migrations and seed data once with setup, add up to three background processes, and link your API docs.
setup≤ 3 processes
R·05
Encrypted secrets
Write-only in the dashboard, paste a whole .env file, added when a preview starts and masked in logs.
write-only.env import
R·06
Approved connections
Allow up to ten outside destinations, like a sandbox database, when your preview needs them.
≤ 10 destinations
V·01
A private HTTPS link
One unguessable link per pull request that stays the same for its whole life.
pr-42-…HTTPS
V·02
No broken links
A new commit takes over only once it's healthy. Until then, the previous version keeps serving.
health-checked
V·03
One living comment
One comment on the pull request, updated from Queued to Building to Ready. It always names the commit it describes.
no spam
V·04
Checks on the commit
A Previa preview check on the exact commit: in progress, then success or failure, right in GitHub.
GitHub checks
V·05
Live build logs
Watch the build as it happens, then copy or download the log. Secrets are masked.
livemasked
V·06
A dashboard that tells the truth
Every pull request's state at a glance. When something can't run, it says why and how to fix it.
Ctrl Klight & dark
C·01
You hold the controls
Build, Retry, Rebuild and Tear down, with a confirmation before anything is removed.
owner only
C·02
Sync on demand
Pull in the latest pull requests from GitHub with one click, whenever you like.
Sync
C·03
Automatic cleanup
Closing or merging removes the preview at once. Forgotten previews expire after 48 hours.
48 h
C·04
Fair queueing
When it's busy, your build waits its turn and starts on its own. It never just fails.
Waiting its turn
C·05
Search & share
Find any repository or pull request fast, and share the exact view with a link.
shareable views
C·06
Sign in with GitHub
No new password. Signing in doesn't give Previa your code; only the repositories you choose do.
you choose
full-stack
Full-stack previews
Not just pages. Databases included.
Add PostgreSQL or Redis, a setup command and up to three background processes to .previewrc.yaml. Previa starts them next to your app, hands over the connection details, and shares the link only when everything is ready.
.previewrc.yamlyour repository root
https://pr-118-x7k2pa-m4q8r1zd.preview.ajaykathwate.dev
your appyour link:3000 · GET /healthz
private to this preview · never public
- 1Servicesare up and answering
- 2Setupruns once
- 3Workersstart
- 4Your apppasses its health check
- 5Linkgoes live
safe
Previa platform
Public internet only
Private network
Isolated preview
Your
PR
PR
Layer 1 of 5 · Isolated preview
Its own space, with firm limits
Each preview runs on its own, without admin rights, on a read-only file system with firm CPU and memory limits.
checking…
Security
Built for code you haven't reviewed yet.
Every pull request is treated as untrusted, even your own team's. Previews are kept apart from each other, from other customers and from Previa itself.
Forks get less
Pull requests from forks never receive your secrets or extra connections.
Secrets stay secret
Encrypted, added only when a preview starts, masked in logs, and never shown again.
Your account stays separate
Previews never run on Previa's own address, so a preview can't touch your sign-in.
Every build is isolated
Each build runs on its own, with limits, and can't reach anything private.
Unguessable links
Each link has a random part. Previews aren't behind a login, so use test data.
Gone when you're done
Merged, closed or expired: the preview and its data are removed.
roadmap
Roadmap
Built in the open, one step at a time.
Available todayIdeas we're exploring
Not built yet · not promisesanswers
FAQ
Questions, answered plainly.
Didn't find yours?
What is Previa?
Previa turns every GitHub pull request into its own live preview: the exact commit, built from your Dockerfile, running at a private HTTPS link that's posted right on the pull request.
What does my repository need?
Two files at its root: a Dockerfile and a .previewrc.yaml. The config can be as short as {}; by default Previa expects your app on port 3000. You can also set a health check path, environment variables and a size.
Which languages and frameworks work?
Anything that runs in a Docker container and answers HTTP: Node.js, Python, Ruby, Go, Java, PHP, static sites and more. APIs work too.
When does a preview get built?
In Manual mode (the default), when you press Build latest commit. In Automatic mode, five minutes after your last push. Either way, Previa checks with GitHub right before building.
How long does a preview live?
Until its pull request is closed or merged, or 48 hours after it was last published. Building again brings it back at the same link.
Is Previa free?
Yes. Previa is free while it's in early access, so you can explore it on your own pull requests.
Does signing in give Previa my code?
No. Signing in only tells Previa who you are. It reads code only in the repositories, public or private, where you install its GitHub App, and only to build previews and post comments and checks.
Is it safe to build pull requests from forks?
Yes. Every build and preview is isolated, and pull requests from forks never receive your secrets or extra connections.
Who can open a preview?
Anyone who has its link. Each link has a random part, so previews can't be guessed, but they aren't behind a login. Use test data and sandbox credentials, never production ones.
What happens to my code?
It's used only to build and run your preview. When the pull request closes or the preview expires, the preview and its data are removed.
What if a build fails?
The comment and check on the pull request say what went wrong, the full build log is one click away, and you can retry whenever you're ready.
How do I get early access?
Make your early-access pass, then send it to Ajay on LinkedIn to claim your spot.
hello
Early access
Ready to see your
pull requests running?
Previa is in early access. If you'd like it on your repositories, or have feedback, ideas or questions, get in touch.
Previa preview: Queued
Queued: builds as soon as it's your turn.
https://pr-42-gc0uy9-k3x9q2ma.preview.ajaykathwate.devcommit 3f9c2a7